User's Guide

Audio Processor Board Instruction Manual 9-9
10 Apply a 1 kHz, -8 dBm input signal, the modulation should be 90%, observe that the
distortion of the transmitted signal is within 5.0%.
11 Slowly increase the input audio signal level to 5 dBm and observe that the modulation
does not go over 100%. This step verifies the correct operation of the ALC .
12 Change 13.8Vdc power supply to 10V and then to 17V, the modulation of the output RF
signal should remain at the same level of 90% ± 7% and distortion should be less then
3%. This step verifies the correct operation of the power regulator on the transmitter
amplifier board.
13 Repeat steps 7 and 9 if required.
14 Supply a 1 kHz, -10 dBm signal to the microphone input. (Note the level restriction of -
25 dBm to 0 dBm.)
15 Adjust the Microphone Input Level Adjust pot (R1) to achieve 50% of RF signal
modulation. Observe that the distortion should be under 5%.
16 Turn off the transmitter. Remove the signal source and replace all the screws.